What are RCA cables used for in car audio?
RCA cables are able to carry audio signals from one device to another, but it usually carries these signals from the speaker to be boosted by the amp. As amplifiers boost low-level signals, it is the RCA cables that carry these signals.
Does quality of RCA cable matter in car audio?
Good RCA cables make a lot of difference for trained ears and a good sound system. On the other hand, using $10 RCA cables on a $1000 system would be unadvisable. Indeed, you should even upgrade your power cable to avoid any unwanted electrical noises.
How long should RCA cables be for car audio?
Many of the RCA cables come in 5 meter lengths, which is about 16 ft. That will do just fine. Anything shorter might not be long enough.